Older T1D Patients Spend Too Much Time in Hypoglycemic State

​​By staff

Minneapolis, MN—Daily hypoglycemia is common in older adults with type 1 diabetes (T1D), according to a new study, and patients often spend more than an hour a day in that state.

A presentation at the annual meeting of the Endocrine Society in New Orleans estimates that the older T1D patients, unaware that their blood sugar has dropped too low, can spend more than 100 minutes a day in the hypoglycemic range, increasing their risk of seizures, loss of consciousness, and death.

“This study of older individuals shows these patients do indeed spend more than an hour per day in a range of hypoglycemia, which puts them at risk for the dangers of low blood glucose,” explained lead researcher Anders L. Carlson, MD, medication director of the International Diabetes Center in Minneapolis. “Those who do not sense when a low blood glucose is occurring as strongly as others can are particularly at risk.”

Researchers note a paucity of data on time spent in hypoglycemia range among adults aged 60 years and older with T1D. To remedy that, they analyzed blinded continuous glucose monitoring (CGM) data collected at baseline from an existing randomized trial. The data from 203 older adults with T1D came from the Wireless Innovations for Seniors With

Diabetes Mellitus (WISDM) study at 22 sites in the United States. In addition to age, eligibility criteria for that trial included no use of real-time CGM in the 3 months prior to enrollment and hemoglobin A1C less than 10%.

Participants were a median age of 68 years, 52% female, and mostly white; 53% of them used insulin pumps. All wore a blinded Dexcom G4 CGM at baseline for up to 21 days to collect at least 240 hours of CGM data. The study team analyzed associations of demographic and clinical characteristics with CGM-measured glucose levels and variability.

Results indicate that older adults spent a median of 5% of time at less than 70 mg/dL (72 minutes per day) and 1.6% of time at less than 54 mg/dL (24 minutes per day). Researchers suggest that impaired hypoglycemia awareness was associated with greater amounts of time spent with glucose levels <70 and <54 mg/dL, with a median percent time <70 mg/dL of 7% versus 5% (101 vs. 72 minutes per day, P = .01) and median percent time <54 mg/dL of 3% versus 1% (43 vs. 14 minutes per day, P = .008) in those with reduced awareness versus those who were aware or uncertain.

In addition, the study found that participants spent a mean 56% of time in the target glucose range of 70 to 180 mg/dL (13.4 hours per day), a median 35% of time above 180 mg/dL (8.4 hours per day), and a median 12% of time above 250 mg/dL (2.8 hours per day).

Overall, participants had a median coefficient of variation (CV) of 42% with a higher CV observed among participants diagnosed younger than age 18 years compared with those with adult onset (P = .02).

“On review of blinded CGM data, older adults (age ≥60 years) with T1D spend over an hour a day in the hypoglycemic range and >100 minutes per day among those with impaired hypoglycemia awareness,” study authors conclude.

“The findings underscore the need for interventions to help reduce the risk of severe hypoglycemia in this age group,” Carlson added.